SDL  2.0
SDL_main.h
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1 /*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2022 Sam Lantinga <slouken@libsdl.org>
4 
5  This software is provided 'as-is', without any express or implied
6  warranty. In no event will the authors be held liable for any damages
7  arising from the use of this software.
8 
9  Permission is granted to anyone to use this software for any purpose,
10  including commercial applications, and to alter it and redistribute it
11  freely, subject to the following restrictions:
12 
13  1. The origin of this software must not be misrepresented; you must not
14  claim that you wrote the original software. If you use this software
15  in a product, an acknowledgment in the product documentation would be
16  appreciated but is not required.
17  2. Altered source versions must be plainly marked as such, and must not be
18  misrepresented as being the original software.
19  3. This notice may not be removed or altered from any source distribution.
20 */
21 
22 #ifndef SDL_main_h_
23 #define SDL_main_h_
24 
25 #include "SDL_stdinc.h"
26 
27 /**
28  * \file SDL_main.h
29  *
30  * Redefine main() on some platforms so that it is called by SDL.
31  */
32 
33 #ifndef SDL_MAIN_HANDLED
34 #if defined(__WIN32__)
35 /* On Windows SDL provides WinMain(), which parses the command line and passes
36  the arguments to your main function.
37 
38  If you provide your own WinMain(), you may define SDL_MAIN_HANDLED
39  */
40 #define SDL_MAIN_AVAILABLE
41 
42 #elif defined(__WINRT__)
43 /* On WinRT, SDL provides a main function that initializes CoreApplication,
44  creating an instance of IFrameworkView in the process.
45 
46  Please note that #include'ing SDL_main.h is not enough to get a main()
47  function working. In non-XAML apps, the file,
48  src/main/winrt/SDL_WinRT_main_NonXAML.cpp, or a copy of it, must be compiled
49  into the app itself. In XAML apps, the function, SDL_WinRTRunApp must be
50  called, with a pointer to the Direct3D-hosted XAML control passed in.
51 */
52 #define SDL_MAIN_NEEDED
53 
54 #elif defined(__GDK__)
55 /* On GDK, SDL provides a main function that initializes the game runtime.
56 
57  Please note that #include'ing SDL_main.h is not enough to get a main()
58  function working. You must either link against SDL2main or, if not possible,
59  call the SDL_GDKRunApp function from your entry point.
60 */
61 #define SDL_MAIN_NEEDED
62 
63 #elif defined(__IPHONEOS__)
64 /* On iOS SDL provides a main function that creates an application delegate
65  and starts the iOS application run loop.
66 
67  If you link with SDL dynamically on iOS, the main function can't be in a
68  shared library, so you need to link with libSDLmain.a, which includes a
69  stub main function that calls into the shared library to start execution.
70 
71  See src/video/uikit/SDL_uikitappdelegate.m for more details.
72  */
73 #define SDL_MAIN_NEEDED
74 
75 #elif defined(__ANDROID__)
76 /* On Android SDL provides a Java class in SDLActivity.java that is the
77  main activity entry point.
78 
79  See docs/README-android.md for more details on extending that class.
80  */
81 #define SDL_MAIN_NEEDED
82 
83 /* We need to export SDL_main so it can be launched from Java */
84 #define SDLMAIN_DECLSPEC DECLSPEC
85 
86 #elif defined(__NACL__)
87 /* On NACL we use ppapi_simple to set up the application helper code,
88  then wait for the first PSE_INSTANCE_DIDCHANGEVIEW event before
89  starting the user main function.
90  All user code is run in a separate thread by ppapi_simple, thus
91  allowing for blocking io to take place via nacl_io
92 */
93 #define SDL_MAIN_NEEDED
94 
95 #elif defined(__PSP__)
96 /* On PSP SDL provides a main function that sets the module info,
97  activates the GPU and starts the thread required to be able to exit
98  the software.
99 
100  If you provide this yourself, you may define SDL_MAIN_HANDLED
101  */
102 #define SDL_MAIN_AVAILABLE
103 
104 #elif defined(__PS2__)
105 #define SDL_MAIN_AVAILABLE
106 
107 #define SDL_PS2_SKIP_IOP_RESET() \
108  void reset_IOP(); \
109  void reset_IOP() {}
110 
111 #endif
112 #endif /* SDL_MAIN_HANDLED */
113 
114 #ifndef SDLMAIN_DECLSPEC
115 #define SDLMAIN_DECLSPEC
116 #endif
117 
118 /**
119  * \file SDL_main.h
120  *
121  * The application's main() function must be called with C linkage,
122  * and should be declared like this:
123  * \code
124  * #ifdef __cplusplus
125  * extern "C"
126  * #endif
127  * int main(int argc, char *argv[])
128  * {
129  * }
130  * \endcode
131  */
132 
133 #if defined(SDL_MAIN_NEEDED) || defined(SDL_MAIN_AVAILABLE)
134 #define main SDL_main
135 #endif
136 
137 #include "begin_code.h"
138 #ifdef __cplusplus
139 extern "C" {
140 #endif
141 
142 /**
143  * The prototype for the application's main() function
144  */
145 typedef int (*SDL_main_func)(int argc, char *argv[]);
146 extern SDLMAIN_DECLSPEC int SDL_main(int argc, char *argv[]);
147 
148 
149 /**
150  * Circumvent failure of SDL_Init() when not using SDL_main() as an entry
151  * point.
152  *
153  * This function is defined in SDL_main.h, along with the preprocessor rule to
154  * redefine main() as SDL_main(). Thus to ensure that your main() function
155  * will not be changed it is necessary to define SDL_MAIN_HANDLED before
156  * including SDL.h.
157  *
158  * \since This function is available since SDL 2.0.0.
159  *
160  * \sa SDL_Init
161  */
162 extern DECLSPEC void SDLCALL SDL_SetMainReady(void);
163 
164 #if defined(__WIN32__) || defined(__GDK__)
165 
166 /**
167  * Register a win32 window class for SDL's use.
168  *
169  * This can be called to set the application window class at startup. It is
170  * safe to call this multiple times, as long as every call is eventually
171  * paired with a call to SDL_UnregisterApp, but a second registration attempt
172  * while a previous registration is still active will be ignored, other than
173  * to increment a counter.
174  *
175  * Most applications do not need to, and should not, call this directly; SDL
176  * will call it when initializing the video subsystem.
177  *
178  * \param name the window class name, in UTF-8 encoding. If NULL, SDL
179  * currently uses "SDL_app" but this isn't guaranteed.
180  * \param style the value to use in WNDCLASSEX::style. If `name` is NULL, SDL
181  * currently uses `(CS_BYTEALIGNCLIENT | CS_OWNDC)` regardless of
182  * what is specified here.
183  * \param hInst the HINSTANCE to use in WNDCLASSEX::hInstance. If zero, SDL
184  * will use `GetModuleHandle(NULL)` instead.
185  * \returns 0 on success, -1 on error. SDL_GetError() may have details.
186  *
187  * \since This function is available since SDL 2.0.2.
188  */
189 extern DECLSPEC int SDLCALL SDL_RegisterApp(const char *name, Uint32 style, void *hInst);
190 
191 /**
192  * Deregister the win32 window class from an SDL_RegisterApp call.
193  *
194  * This can be called to undo the effects of SDL_RegisterApp.
195  *
196  * Most applications do not need to, and should not, call this directly; SDL
197  * will call it when deinitializing the video subsystem.
198  *
199  * It is safe to call this multiple times, as long as every call is eventually
200  * paired with a prior call to SDL_RegisterApp. The window class will only be
201  * deregistered when the registration counter in SDL_RegisterApp decrements to
202  * zero through calls to this function.
203  *
204  * \since This function is available since SDL 2.0.2.
205  */
206 extern DECLSPEC void SDLCALL SDL_UnregisterApp(void);
207 
208 #endif /* defined(__WIN32__) || defined(__GDK__) */
209 
210 
211 #ifdef __WINRT__
212 
213 /**
214  * Initialize and launch an SDL/WinRT application.
215  *
216  * \param mainFunction the SDL app's C-style main(), an SDL_main_func
217  * \param reserved reserved for future use; should be NULL
218  * \returns 0 on success or -1 on failure; call SDL_GetError() to retrieve
219  * more information on the failure.
220  *
221  * \since This function is available since SDL 2.0.3.
222  */
223 extern DECLSPEC int SDLCALL SDL_WinRTRunApp(SDL_main_func mainFunction, void * reserved);
224 
225 #endif /* __WINRT__ */
226 
227 #if defined(__IPHONEOS__)
228 
229 /**
230  * Initializes and launches an SDL application.
231  *
232  * \param argc The argc parameter from the application's main() function
233  * \param argv The argv parameter from the application's main() function
234  * \param mainFunction The SDL app's C-style main(), an SDL_main_func
235  * \return the return value from mainFunction
236  *
237  * \since This function is available since SDL 2.0.10.
238  */
239 extern DECLSPEC int SDLCALL SDL_UIKitRunApp(int argc, char *argv[], SDL_main_func mainFunction);
240 
241 #endif /* __IPHONEOS__ */
242 
243 #ifdef __GDK__
244 
245 /**
246  * Initialize and launch an SDL GDK application.
247  *
248  * \param mainFunction the SDL app's C-style main(), an SDL_main_func
249  * \param reserved reserved for future use; should be NULL
250  * \returns 0 on success or -1 on failure; call SDL_GetError() to retrieve
251  * more information on the failure.
252  *
253  * \since This function is available since SDL 2.24.0.
254  */
255 extern DECLSPEC int SDLCALL SDL_GDKRunApp(SDL_main_func mainFunction, void *reserved);
256 
257 #endif /* __GDK__ */
258 
259 #ifdef __cplusplus
260 }
261 #endif
262 #include "close_code.h"
263 
264 #endif /* SDL_main_h_ */
265 
266 /* vi: set ts=4 sw=4 expandtab: */
void SDL_SetMainReady(void)
SDLMAIN_DECLSPEC int SDL_main(int argc, char *argv[])
#define SDLMAIN_DECLSPEC
Definition: SDL_main.h:115
int(* SDL_main_func)(int argc, char *argv[])
Definition: SDL_main.h:145
int SDL_RegisterApp(const char *name, Uint32 style, void *hInst)
void SDL_UnregisterApp(void)
uint32_t Uint32
Definition: SDL_stdinc.h:226